As in the thread on WW2 African notes - chemical alterations of seal colors can be done which can at least for awhile, fool some pretty sophisticated people. This note was encapsulated by PMG and was accepted for auction by Heritage: If a true error it would be spectacular, unique and quite beautiful - even though I don't collect errors I would have wanted to bid on it. Alas it was later determined to be chemically altered. Still pretty cool though if you ask me.
I'm surprised the note made it as far along as it did before anyone realized it was altered. If it were genuine then hundreds of thousands of these would have been made. If the BEP didn't notice before releasing them then they would have no doubt been noticed in short order when they were shipped out to be distributed by local banks. And if the banks didn't notice their customers would have at some point soon after. The media would have been informed, the error reported in coin & currency news publications, and the BEP would have been compelled to issue a validating statement.
I had my doubts about that note from the moment I first saw it over 10 years ago. It originally auctioned for $747 and the owner has declined offers for twice the price. This is the auction description from Heritage.
I would love to know what chemical would do that, In fact I can not come up with one that is that selective, and any residue would be determinable by modern instruments. I doubt the bill would even have to be removed for the testing. I am not convinced it is alteration and wonder what information was presented for it and their reasoning. Jim